From 89afc3f322b53e3fc8e361b76050c63152258319 Mon Sep 17 00:00:00 2001
From: sgoudham <sgoudham@gmail.com>
Date: Wed, 22 Dec 2021 09:17:48 +0000
Subject: [PATCH] Experiment With Multiple Threads

---
 src/list.c      | 25 +++++++++++++++++++++++--
 src/list.h      |  9 ++++++++-
 src/test/test.c | 21 +++++++++++++--------
 3 files changed, 44 insertions(+), 11 deletions(-)

diff --git a/src/list.c b/src/list.c
index f314153..51b0d26 100644
--- a/src/list.c
+++ b/src/list.c
@@ -21,6 +21,7 @@ typedef struct list {
     int *_array;
     int _currentSize;
     int _maxSize;
+    pthread_mutex_t simpleMutex;
 } List;
 
 int errorCodes[ERRNO_SIZE] = {
@@ -31,8 +32,13 @@ int errorCodes[ERRNO_SIZE] = {
         ERRNO_005
 };
 
-List *newList() {
-    return List_createList(10, -1);
+List *List_new() {
+    List *list = List_createList(10, -1);
+    if (!list) {
+        return NULL;
+    }
+    pthread_mutex_init(&list->simpleMutex, NULL);
+    return list;
 }
 
 int List_get(List *list, int index) {
@@ -49,6 +55,10 @@ int List_append(List *list, int element) {
         }
     }
 
+    // Beginning of Critical Section
+    pthread_mutex_lock(&(list->simpleMutex));
+    printf("\nMutex Locked!");
+
     if (list->_currentSize + 1 == list->_maxSize) {
         list->_maxSize *= 2;
         int *temp = realloc(list->_array, list->_maxSize * sizeof(int));
@@ -59,6 +69,10 @@ int List_append(List *list, int element) {
     }
     list->_array[++list->_currentSize] = element;
 
+    // End of Critical Section
+    pthread_mutex_unlock(&(list->simpleMutex));
+    printf("\nMutex Unlocked!");
+
     return 0;
 }
 
@@ -190,6 +204,10 @@ int List_length(List *list) {
 }
 
 void List_print(List *list) {
+
+    // Beginning Of Critical Section
+    pthread_mutex_lock(&(list->simpleMutex));
+
     printf("[");
     for (int i = 0; i < list->_currentSize + 1; i++) {
         if (i == list->_currentSize) {
@@ -199,6 +217,9 @@ void List_print(List *list) {
         }
     }
     printf("]");
+
+    // End Of Critical Section
+    pthread_mutex_unlock(&(list->simpleMutex));
 }
 
 void List_destroy(List **list) {
diff --git a/src/list.h b/src/list.h
index 886b6ef..095214d 100644
--- a/src/list.h
+++ b/src/list.h
@@ -11,7 +11,14 @@
 
 typedef struct list List;
 
-List *newList();
+/*
+ * Function: List_new
+ * ----------------------------
+ *  Return a new list that has been dynamically allocated memory on the heap
+ *
+ *  returns: int (Pointer To List)
+ */
+List *List_new();
 
 /*
  * Function: List_get
diff --git a/src/test/test.c b/src/test/test.c
index 1195c9b..54e73de 100644
--- a/src/test/test.c
+++ b/src/test/test.c
@@ -1,3 +1,4 @@
+#include <unistd.h>
 #include "src/list.h"
 #include "pthread.h"
 #include "string.h"
@@ -14,7 +15,7 @@ void printSuccess(const char method[]) {
 
 void shouldReturnListLengthZero() {
     // Arrange
-    List *list = newList();
+    List *list = List_new();
 
     // Act -> Assert
     assert(List_length(list) == 0);
@@ -25,7 +26,7 @@ void shouldReturnListLengthZero() {
 
 void shouldReturnListLengthTwo() {
     // Arrange
-    List *list = newList();
+    List *list = List_new();
     List_append(list, 1);
     List_append(list, 2);
 
@@ -38,7 +39,7 @@ void shouldReturnListLengthTwo() {
 
 void shouldReturnSortedList() {
     // Arrange
-    List *list = newList();
+    List *list = List_new();
     List_append(list, 10);
     List_append(list, 9);
     List_append(list, 8);
@@ -80,19 +81,23 @@ int main() {
 //    shouldReturnListLengthZero();
 //    shouldReturnListLengthTwo();
 //    shouldReturnSortedList();
-    List *list = newList();
 
-    pthread_t pthreads[5];
-    for (int i = 0; i < 5; i++) {
+    List *list = List_new();
+
+    pthread_t pthreads[2];
+    for (int i = 0; i < 2; i++) {
+        printf("\nElement To Insert -> %i", i);
         Arguments args = {list, i};
         pthread_create(&pthreads[i], NULL, append, &args);
     }
 
-    for (int i = 0; i < 5; i++) {
-        List_print(list);
+    for (int i = 0; i < 2; i++) {
         pthread_join(pthreads[i], NULL);
     }
 
+    printf("\n\nList: \n");
+    List_print(list);
+
     return 0;
 }